A comparison of chitosan-silica and sodium starch glycolate as disintegrants for spheronized extruded microcrystalline cellulose pellets

Abstract

Chitosan-silica coprecipitate (C-S) has recently been proposed as a tablet disintegrant. In this study we compared it with a 1:1 physical mixture of chitosan and silica (C/S) at the same composition as the coprecipitate, and with the widely used commercial disintegrant sodium starch glycolate (SSG), as regards to its behavior in spheronized extruded pellets of microcrystalline cellulose (MCC) containing hydrochlorothiazide as a typical poorly water-soluble drug. In all three cases, possible synergism between the disintegrant (0–5%) and sorbitol (0–50%) was also evaluated. All the formulations examined exhibited appropriate morphology and had satisfactory mechanical and flow properties. Drug release depended mainly on sorbitol content, however C-S accelerated drug release at all sorbitol levels (the fastest release was from 50% sorbitol pellets with C-S, which disintegrated), whereas C/S did not vary drug release from pellets, and SSG depressed drug release, especially from 50% sorbitol pellets.

Keywords::

• Chitosan-silica
• sodium starch glycolate
• pellet
• MCC
• disintegrant
• drug release

Acknowledgements

The authors would like to thank Roquette Laisa España, S.A. (Spain) and Evonik Industries for the generous gift of samples of sorbitol and colloidal silica.

Declaration of interest

This work was supported by grant 07CSA006203PR from the CII (Xunta de Galicia). The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this paper.